Former vice president Joe Biden notched an endorsement from a major environmental group — and is signaling he will expand his climate plan in an effort to win over young voters who see rising global temperatures as a generational crisis.

The political arm of the League of Conservation Voters, a Washington-based green group that has spent tens of millions of dollars in recent election cycles to help elect Democrats to office, announced Monday that it is backing the presumptive Democratic nominee in what looks to be a tough fight against President Trump.

Drastically reducing greenhouse gas emissions “is going to take leadership,” said Carol Browner, the chair of LCV’s board of directors. “And I have every confidence that the vice president will provide that.”

The endorsement from the LCV could encourage other green groups who supported Biden’s rivals in a crowded primary to fall in line. The group hopes to prevent Trump, who has repeatedly denied the scientific consensus that human activity is warming the planet, from winning a second term.

“Scientists tell us we have 10 years” to get climate change under control, said Browner, who ran the Environmental Protection Agency for eight years under former president Bill Clinton. “We’re going to have to not just put back in place all the stuff that Trump undid from the Obama years, we’re going to have to do more.”

Biden said in a statement that he was “honored” to have the LCV’s endorsement. “For me, this is personal,” said Biden, a former senator from Delaware. “I live in a state that’s dealing first hand with the impacts of climate change and impacts of pollution on kids and families. I’m going to fight for my grandkids.”

But even after the departure of Sen. Bernie Sanders (I-Vt.) from the race this month, Biden may face a tough time winning over some environmental activists on the party’s left who say his plan for tackling climate change falls short of what is needed to forestall a devastating rise in temperatures this century.

Biden, without offering specifics, said in his statement that he wanted to adopt ideas from climate activists and set other “new, concrete goals” for combating climate change before the end of the decade.

“In the months ahead, expanding this plan will be one of my key objectives,” Biden said. “I know this is an issue that resonates with many, including young people and those who have seen floods, fires, and drought destroy lives and livelihoods.”

Biden’s original 22-page climate plan, released last June, calls for the United States to achieve net-zero emissions by at least 2050, all while creating 10 million well-paying jobs and helping fossil fuel workers transition to a clean-energy economy.

Stef Feldman, Biden’s policy director, said the campaign “always had an expectation that we will continue to build upon that policy.”

Biden scored his first endorsement from an environmental group, the National Wildlife Federation’s political arm, after posting big wins in last month’s Super Tuesday primary.

But most green groups who backed a candidate endorsed either Sanders or fellow liberal stalwart Sen. Elizabeth Warren (Mass.). A handful of local chapters of the Sunrise Movement, which endorsed Sanders, went so far as to insist that it would never back Biden even if he won the nomination.

After years of being an afterthought at the polls, climate change emerged as a top issue in the Iowa, New Hampshire and Nevada primaries, ranking second in importance after health care in exit polling.

But it remains to be seen whether the slow-burning crisis of global warming will still be top of mind for voters in November given the coronavirus pandemic, which is raising widespread public health concerns and shuttering the economy.

Even though Trump’s bully pulpit is now arguably bigger than ever, LCV leaders predict that Trump’s handling of the latest crisis will prove unpopular with those who already oppose his moves to dismantle environmental regulations for the past three years.

Tiernan Sittenfeld, the LCV’s senior vice president of government affairs, says the two issues are tied together since both have to do with heeding the advice of scientists.

Trump “ignores experts. He insists that he knows better,” Sittenfeld said. “He clearly is a danger to the health and safety of all people in this country.”

The LCV pumped more than $80 million into the 2018 election to help Democrats win control of the House. “That was a record,” Browner said, “and we believe we can set another record this time.”

The group has also poured $14 million into an online advertising and direct-mail campaign attacking Trump’s environmental record in six swing states — Arizona, Florida, Michigan, North Carolina, Pennsylvania and Wisconsin.